The extensive wetland formed by the Mar Chiquita lake and Dulce River basin is home to three of the six species of flamingos that exist in the world. In the framework of the simultaneous census of high-Andean flamingos (Phoenicoparrus andinus and Phoenicoparrus jamesi) and a monitoring project of Chilean flamingos (Phoenicopterus chilensis), we carried out summer and winter aerial surveys in 2018. Given the magnitude of this wetland, aerial surveys are necessary to cover known flamingo habitats. During the summer survey, we counted 296,916 Chilean flamingos, 5,746 Andean flamingos, and 2,244 puna flamingos. During the winter survey we counted 258,650 Chilean flamingos, 11,607 Andean flamingos, and 4,277 puna flamingos. This wetland concentrates the highest number of Chilean flamingos and is one of the only sites outside the Andes where the three species coexist. These data collected are extremely important for the justification of the creation of the Ansenuza National Park.